Natura - nature
   actualia - actual entities
     Mundus Plinius - physical world
       naturalia - natural bodies
         [[crown] organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
           [Eukaryota Chatton, 1925 - eukaryotes] see Domain Eukaryota Chatton, 1925
             [Phylum Alveolata Cavalier-Smith, 1991] see Superphylum Alveolata Cavalier-Smith, 1991
               [Subphylum Ciliophora Doflein, 1901] see Phylum Ciliophora Doflein, 1901
                 [Class Ciliata] see [unranked] ciliates
                   [Order Calycata]
                   1 [Order Holotricha]
                   2 [Order Peritricha Stein, 1859]
                   3 [Order Spirotricha]
                   3.1 [Order Heterotricha Stein, 1859] see Suborder Heterotricha Stein, 1859
                   3.2 [Order Hypotricha] see Suborder Hypotricha Stein, 1859
                   4 [Order Chonotricha]
                   5 Order Suctoria